MySQL  8.0.21
Source Code Documentation
ut0crc32.h
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26 
27 /** @file include/ut0crc32.h
28  CRC32 implementation
29 
30  Created Aug 10, 2011 Vasil Dimov
31  *******************************************************/
32 
33 #ifndef ut0crc32_h
34 #define ut0crc32_h
35 
36 #include "univ.i"
37 
38 /** Initializes the data structures used by ut_crc32*(). Does not do any
39  allocations, would not hurt if called twice, but would be pointless. */
40 void ut_crc32_init();
41 
42 /** Calculates CRC32.
43  @param ptr - data over which to calculate CRC32.
44  @param len - data length in bytes.
45  @return CRC32 (CRC-32C, using the GF(2) primitive polynomial 0x11EDC6F41,
46  or 0x1EDC6F41 without the high-order bit) */
47 typedef uint32_t (*ut_crc32_func_t)(const byte *ptr, ulint len);
48 
49 /** Pointer to CRC32 calculation function. */
51 
52 /** Pointer to CRC32 calculation function, which uses big-endian byte order
53 when converting byte strings to integers internally. */
55 
56 /** Pointer to CRC32-byte-by-byte calculation function (byte order agnostic,
57 but very slow). */
59 
60 /** Flag that tells whether the CPU supports CRC32 or not.
61 The CRC32 instructions are part of the SSE4.2 instruction set. */
62 extern bool ut_crc32_cpu_enabled;
63 
64 #endif /* ut0crc32_h */
ut_crc32_func_t ut_crc32_legacy_big_endian
Pointer to CRC32 calculation function, which uses big-endian byte order when converting byte strings ...
Definition: crc32.cc:133
ut_crc32_func_t ut_crc32
Pointer to CRC32 calculation function.
Definition: crc32.cc:129
bool ut_crc32_cpu_enabled
Flag that tells whether the CPU supports CRC32 or not.
Definition: crc32.cc:153
uint32_t(* ut_crc32_func_t)(const byte *ptr, ulint len)
Calculates CRC32.
Definition: ut0crc32.h:47
void ut_crc32_init()
Initializes the data structures used by ut_crc32*().
Definition: crc32.cc:662
ut_crc32_func_t ut_crc32_byte_by_byte
Pointer to CRC32-byte-by-byte calculation function (byte order agnostic, but very slow)...
Definition: crc32.cc:137
unsigned char byte
Blob class.
Definition: common.h:159